It was a difficult storm to forecast in both the long and short time ranges with the degree of jet stream blocking over the North Atlantic-Greenland in question in the days prior to the event as well as the level of phasing that would occur between disturbances in both the northern and southern branch jet streams over the United States. The subtleties of where these major features would set-up would mean the difference between a storm tracking hundreds of miles off-shore or one coming in close to the coast producing heavy snow, high wind, and coastal flooding in the Northeast. The later solution obviously verified with a powerful coastal storm passing very near Cape Cod and the Island early Monday morning December 27th. The storm "Bombed" or in other words, rapidly intensified Sunday afternoon and night with central pressure falls averaging 2-3mb/hour, dropping ultimately to a pressure of 966mb (category two hurricane range.) A fully phased northern and southern branch jet stream trough, with strong cut-off low pressure in the upper levels, along with a powerful dual coupled jet stream, and the strong temperature contrast zone along the coast, which is common this time of the year, all fueled the massive storm as it pounded much of the mid Atlantic coastal plain with heavy snow ultimately bringing a true blizzard to New Jersey, New York City, and much of New England from late Sunday through Monday morning.

The storm locally, however, was not an equal opportunity snow producer with the very sharp back edge to the snow shield cutting across the eastern Mohawk valley and western Catskills. The accumulated snowfall gradient from northwest to southeast across the 21 County WRGB coverage area was very tight, from no snow in the much of the Mohawk valley and Adirondacks, to a wide area of 18"-24" in the mid Hudson valley and western New England.

The storm began over the local area during the mid afternoon as the initial bands of moderate to heavy snow propagated north into Dutchess, Litchfield, Columbia, and Berkshire Counties between roughly 3pm and 6pm. Snowfall rates quickly climbed to 1"-2" per hour with the initial snow band in these counties into the evening. Snow began to fall in the immediate Capital Region around 7pm with a slow northward and subtle westward shift in the snow zone through midnight. Strong small scale banding produced locally heavy snow which coupled with north-northeast winds gusting to 35 mph, created near blizzard conditions in whiteouts in the mid Hudson valley and western New England through then night.

Albany Level II Lowest Tilt Doppler Radar Image: 8:48pm Sunday December 26, 2010: Even early in the storm, the very sharp back edge to the snow shield had become established with nothing more than flurries flying in the western Catskills, Mohawk valley and Adirondacks. Snowfall rates, however, up to 2" per hour were in progress at this time in Bennington, Berkshire, Litchfield, Rensselaer, Columbia, and Dutchess counties, indicated by the dark green banded regions on the radar image.

A fairly steady state snow scenario continued in the Hudson valley and western New England through early Monday morning, with a slight westward extension of the snow into Schoharie county and north to Warren County. In the Hudson valley, the narrow snow band intensified through the pre-dawn hours bringing renewed bursts of 2" per hour snowfall rates affecting parts of the immediate Capital Region through the Monday morning commute. The continued rapid drop in air pressure around the off shore storm continued to tighten the air pressure gradient over the local area which supported an increase in wind speeds through Monday with gusts ranging from 40-45 mph.

Albany Level II Lowest Tilt Doppler Radar Image: Midnight Monday December 27, 2010: Note the overall little change in the position of the narrow axis of heavy snow as compared to the 8:48pm image. This snow band remained nearly stationary in response to the slow movement and slight hooking to the left of the coastal storm as the parent upper level storm captured it. Also note the relatively dry region over central New England, immediately east of Berkshire county. A large gravity wave is believed to have created a zone of sinking air to the northwest of the storm center which effectively dried up the snow over a large portion of central new England for a time late Sunday night through early Monday morning. Snowfall, however, was enhanced along the leading edge of the gravity wave, in the zone over the Hudson valley, where there was also a brief period of stronger surface winds between approximately 10:10pm and 11:05pm, where wind gusts of 40+ mph were recorded in East Greenbush, Bennington, VT, as well as in Columbia, Berkshire, and Litchfield counties. (Gravity waves area common in the atmosphere often leading to interesting cloud formations. Large gravity waves, that rapidly intensifying synoptic scale storms can produce, are not predictable and can have big impacts on the sensible weather at the surface in terms of wind and the character and behavior of precipitation, enhancing it along the leading edge of the wave while drying it up behind the wave.)

Moderate to heavy snow in the Hudson valley and western New England Monday morning broke up with the last of it done by noon. Strong sunshine developed over the region during the afternoon with howling northwest winds gusting to 40-45 mph. Significant blowing and drifting snow occurred in the heavy snow zones with wind chills near 0° into the night.

WeatherNet Storm Total Snowfall Reports for the December 26-27, 2010 Storm